A stent is generally a medical device for treating various diseases caused by stenosis or occlusion of a blood vessel or another in vivo lumen. The stent is a medical device, which has, for example, an expandable mesh structure part, expands a lesion site such as a stenosis or occlusion site from the inside, and is indwelled in the lesion site to maintain an inside diameter of a lumen with the lesion.
The stent is used in a living body, and thus once the stent is inserted into the body, the position thereof cannot be visually confirmed. In usual, accordingly, markers including a radiopaque material (hereinafter referred to as marker inserts) are provided on pre-determined positions on the stent, and a medical treatment is advanced while exact positions of the markers are confirmed under an X-ray illumination.
A method in which marker inserts are pressure fitted to an opening of a marker housing provided on a stent (Patent Document 1 and Patent Document 2); a method in which marker inserts are welded to a stent using a laser (Patent Document 3), or a method in which marker inserts are formed in a structural element of a stent by using a plating method (Patent Document 4), or the like has been proposed as a method for attaching the marker inserts to the stent. Of these, the method in which the marker inserts are pressure fitted to the opening of the marker housing is preferably used, because it is a simple method requiring no particular, special facilities or techniques, and less galvanic corrosion occurs.